Source: nfs-utils Version: 1:1.3.4-2.1 Tags: patch https://tracker.debian.org/pkg/nfs-utils mentions "Problems while searching for a new upstream version". The reason turns out to be that the version string pattern in debian/watch matches .. as well as 2.3.1 etc. and uscan treats .. as newest. A minimal fix (tested) is to change /([\.\d]+)/ to /(\d[\.\d]*)/ . There may be better solutions.
Incidentally, the latest upstream release of nfs-utils is 2.3.1. Debian sid still has 1.3.4.